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    I lose the IPv6 connection after reboot / if the network goes down

    Scheduled Pinned Locked Moved IPv6
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    • R
      root1ng LAYER 8
      last edited by

      Hello,

      I also have a problem with the IPv6 connection on the WAN, but also on the LAN, in the following situation:

      • I use IPv6 (DHCPv6) on the WAN interface, sent prefix hint checked, prefix delegation 56, RA set to Managed, priority to high
      • In this situation, after I restart the router or the modem fails, the IPv6 connection is lost until I restore it manually from Status - Interfaces, and after the restoration no address is assigned to me on the LAN interface, I also tried with restart manually at the DHCPv6 server, but without any success, I also tried restarting the associated systems, but also without success.
        What can I do to make it work "automatically" if the network goes down or after the system has restarted.
      1 Reply Last reply Reply Quote 0
      • R
        root1ng LAYER 8
        last edited by

        Edit:

        I found the solution for the WAN interface, for those who still have the same problem, you must check "Do not wait for a RA" and it will work without problems even after restart / if the modem fails, but I keep facing a problem RA is set to Managed , Router priority on High, DHCPv6 server ON for the LAN interface, but no IP address is assigned to me for LAN users or there is a chance that it will be assigned to me at a given moment, and then the link will disappear.
        What can I do to allocate addresses on the correct network? And not to lose them on restart?

        JKnottJ 1 Reply Last reply Reply Quote 0
        • R
          root1ng LAYER 8
          last edited by

          Edit 2:

          I don't mind having the private IPv6 address, if it is possible to get the address that is associated with the WAN interface, it wouldn't be a problem for me.

          1 Reply Last reply Reply Quote 0
          • JKnottJ
            JKnott @root1ng
            last edited by

            @root1ng

            Why not use SLAAC on the LAN side? No need for DHCP6. I use unmanaged.

            PfSense running on Qotom mini PC
            i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
            UniFi AC-Lite access point

            I haven't lost my mind. It's around here...somewhere...

            R 1 Reply Last reply Reply Quote 1
            • R
              root1ng LAYER 8 @JKnott
              last edited by

              @JKnott said in I lose the IPv6 connection after reboot / if the network goes down:

              @root1ng

              Why not use SLAAC on the LAN side? No need for DHCP6. I use unmanaged.

              So should I use SLAAC on the LAN interface (Use ipv4 as parent checked?) Is the DHCPv6 server running on your LAN interface? If you can, when you answer, add some pictures of your config in the lan interface, RA, and dhcpv6 if necessary.

              JKnottJ 1 Reply Last reply Reply Quote 0
              • JKnottJ
                JKnott @root1ng
                last edited by

                @root1ng

                I don't use DHCPv6, as there's no need for it with SLAAC. Also, Android devices don't work with it.

                Here's my RA settings. Don't worry about the subnets box, unless you also have ULA on your LAN.

                ded93396-2b1e-4c0e-b839-b63b92397f19-image.png

                PfSense running on Qotom mini PC
                i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
                UniFi AC-Lite access point

                I haven't lost my mind. It's around here...somewhere...

                R 1 Reply Last reply Reply Quote 0
                • R
                  root1ng LAYER 8 @JKnott
                  last edited by

                  @JKnott said in I lose the IPv6 connection after reboot / if the network goes down:

                  @root1ng

                  I don't use DHCPv6, as there's no need for it with SLAAC. Also, Android devices don't work with it.

                  Here's my RA settings. Don't worry about the subnets box, unless you also have ULA on your LAN.

                  ded93396-2b1e-4c0e-b839-b63b92397f19-image.png

                  I disabled the DHCPv6 server, changed the RA to Unmanaged, but when I want to enable SLAAC on the LAN interface I can't do it, the error attached below.

                  Screenshot_3.png

                  R 1 Reply Last reply Reply Quote 0
                  • R
                    root1ng LAYER 8 @root1ng
                    last edited by

                    Edit:

                    I found the solution, I disabled the DHCPv6 server, RA on Assisted and Priority on High, and on the LAN interface I left it on Track Interface. It works without problems even after the restart.

                    Thanks! @JKnott

                    1 Reply Last reply Reply Quote 0
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